High-velocity Impact Location on Aircraft panels Using Macro-fiber Composite piezoelectric Rosettes

In this article, an approach based on an array of macro-fiber composite (MFC)transducers arranged as rosettes is proposed for high-velocity impact location on isotropic andcomposite aircraft panels. Each rosette, using the directivity behavior of three MFC sensors,provides the direction of an incoming wave generated by the impact source as a principalstrain angle. A minimum of two rosettes is sufficient to determine the impact location byintersecting the wave directions. The piezoelectric rosette approach is easier to implement thanthe well-known time-of-flight-based triangulation of acoustic emissions because it does notrequire knowledge of the wave speed in the material. Hence, the technique does not have thedrawbacks of time-of-flight triangulation associated to anisotropic materials or tapered sections.The experiments reported herein show the applicability of the technique to high-velocityimpacts created with a gas-gun firing spherical ice projectiles.